Anticorrosive



Patented June 9, 1942 ANTICORROSIVE Paul R. Van Ess, Berkeley, Calif.,assignor to Shell Development Company, San Francisco, Calif., acorporation of Delaware No Drawing. Application November 18, 1940,

Serial No. 366,148

7 Claims.

This invention deals with the use of alpha naphthyl ethers as additionagents to hydrocarbon oils and other organic substances. I havediscovered that the presence of these compounds in suitable amountsreduces or inhibits the corrosiveness toward metallic surfaces of suchhydrocarbon oils and other organic substances as possess thisobjectionable property.

corrosiveness of organic substances may be inherent in their chemicalstructure or composition, or may be induced by oxidation. Either type ofcorrosiveness may be reduced, and in many instances be completelyinhibited.

Suitable alpha naphthyl ethers are particularly the symmetrical dialphanaphthyl ether, the phenyl and alkyl phenyl alpha naphthyl ethers, suchas tolyl, xylyl, trimethyl phenyl, tetramethyl phenyl, methyl ethylphenyl, n-propyl phenyl, isopropyl phenyl, primary, secondary andtertiary butyl or amyl phenyl, ditertiary butyl phenyl, methylditertiary butyl phenyl, tritertiary butyl phenyl, ditertiary amylphenyl, methyl ditertiary amyl phenyl, tritertiary amyl phenyl, etc.,alpha naphthyl ethers; and alkyl or aralkyl alpha naphthyl ethers, suchas methyl, ethyl, n-propyl, isopropyl, primary, secondary or tertiarybutyl, primary, secondary or tertiary amyl, hexyl, benzyl, etc., alphanaphthyl ethers. If desired, the aromatic nucleus or nuclei, e. g., thenaphthyl radical, may contain one or several alkyl radicals.

, It is of interest to note that the corresponding beta naphthyl ethers,and particularly the dibeta naphthyl ether, have very little inhibitingproperties, and in some instances have been found to aggravatecorrosiveness of substances to which they are added.

The alpha naphthyl ethers of this invention are thermally quite stable,and therefore are useful as addition agent -to a large number ofsubstances which are in need of improvement with regard to reduction ofcorrosiveness. may be added to gasolines, kerosenes, diesel fuels,lubricants, electrical oils, or to non-hydrocarbon substances such asfats, fatty acids. soaps, naphthenate driers, essential oils. extractsof pyrethrum, or other insecticides which lose their potency on exposureto air. etc. Of particular interest is the use of the alpha naphthylethers in lubricating oils containing corrosion-inducing amounts, e. g.,from about .1 of oil-soluble detergents such as salts of polyvalentmetals, more particularly of Mg, Ca, Sr, Ba, Zn, Cd, Al, Sn, Pb, Cr, Mn,Fe, Ni, Co, Cu. with organic acids such as fatty acids, fatty acidshaving attached aromatic radicals as phenyl, hydroxy phenyl, benzyl,benzal, etc., radicals; naphthenic acids, acids obtained from naturalwaxes as montan wax, carnauba wax. candelilla wax, etc., acids obtainedby oxidation of paraflin wax, acids obtained by hydrolysis of rosin oilor tall oil, alkyl- Thus they.

ated benzoic, hydroxy benzoic, naphthoic, etc., acids, sulfonic acids,such as so-called mahogany acids, etc. It is known that these soapscause lubricating oils to become more or less corrosive, particularly toalloy bearings, such as copperlead, cadmium-silver, cadmium-nickel, etc.

The amounts of the ethers to be added varies somewhat depending upon theoriginal corrosiveness or upon the tendency of the substance to increasein corrosiveness during storage or use or both. Thus, while lubricatingoils and the like may require the use of amounts in excess of .2%

and up to 5 to 10% to insure continued non-corrosiveness, particularlyif such lubricating oils should contain corrosive addition compounds,smaller amounts usually are suflicient to inhibit cases of slightcorrosiveness as is normal for example in gasolines, kerosenes, etc. inwhich amounts varying from .001% to 1% are normally sufilcient.

As against alpha-naphthol, beta-naphthol, and many phenolic inhibitors,the alpha-naphthyl ethers have the advantage of being color stable inthe presence of alkali. Many compounded lubricating oils for internalcombustion engines contain alkaline detergents, and in the presence offree alkali the naphthols in particular turn to weird hues, as purple,green or blue.

The following example further illustrates my invention:

Samples of lubricating oils were subjected to a thrust-bearing corrosiontest to determine their corrosiveness. In this test, a hardened steeldisc The bearings reported below consisted of copper-lead alloy. Theoils tested were of the type of anti-ringsticking diesel lubricating oilconsisting of a 55 V. I. mineral lubricating oil S. A. E. 30 andcontaining a detergent soap which caused the oil to be quite corrosive.For comparison, the corrosiveness of the straight mineral oil is alsoshown:

Bearing loss, on mgJsq. cm.

Mineral oil 0. 20 Mineral nil+2. 5% calcium petroleum sulfonate 5. 7Mineral oil+2.5% calcium petroleum sulfonato+l% (ii-alpha naphthyl etherO. ()9 Mineral oil+2.5% calcium petroleum sulfonate+1% di-beta naphthylother l0. 0

I claim as my invention: 1. A non-corrosive lubricating oil composition4. The composition of claim 3 wherein said small amount is between .196-5% 5. A non-corrosive lubricating oil composition comprising alubricating oil which normally causes corrosion containing dissolved asmall amount 01' phenyl alpha naphthyl ether.

6. A non-corrosive lubricating oil composition of claim 3 in which theethers are present in amounts ranging from .001% to 10%.

7. A non-corroslve-lubricating oil composition comprising a lubricatingoil which normally causes corrosion containing dissolved a small amountof (ii-alpha naphthyl ether.

PAUL R. VAN ESS.

